Six people were injured, including one person in a serious condition. One victim “was struck in the throat by a shard of glass and (another) was stabbed in the back”, a police source told local daily Le Parisien.

Another source said a bread knife with a 20 cm blade and traces of blood was also found on the ground. The source said some of the victims were bystanders with no connection to the football fan scene.

Police seized knives and other weapons, along with balaclavas and padded gloves.

“These are certainly fringe groups, as the vast majority of Nice supporters are due to arrive in Paris today,” said Philippe Diallo, the head of the French Football Federation, speaking on France Info radio.

“This is everything we dislike about football – namely violence – when a French Cup final is supposed to be a celebration,” he added.

Paris Mayor Emmanuel Grégoire accused Nice fans, “some of whom are known to have links to the far right”, of “accosting and violently attacking” Parisians.

Friday’s final at the Stade de France has been labelled “high-risk” due to the animosity between Nice and supporters of local giants Paris Saint-Germain, with over 2,000 police officers deployed.

Pitch invasions, run-ins with fans

The violence has cast a shadow over the final showdown against northern club Lens, whose remarkable season has been a polar opposite of Nice’s.

Based in the eponymous football-crazy former mining town, Lens finished second to all-conquering PSG in Ligue 1, falling not far short of a first French title since 1998. Now they are hoping to win the French Cup for the first time in their history, having lost all three previous final appearances.

Victory for the “Sang et Or” (Blood and Gold, after their red and yellow jersey) on Friday would complete a superb run which has already seen them qualify for the Champions League.

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Nice, in contrast, ended their Ligue 1 campaign in the relegation play-off place after winning just two of their last 24 games. Last week’s 0-0 draw with bottom club Metz ended with angry fans invading the pitch, throwing smoke bombs and forcing players to run to the dressing room for cover.

The Riviera club must win a two-legged play-off next week against Saint-Etienne to remain in Ligue 1. They have been ordered to play the home leg behind closed doors as a punishment following the pitch invasion.

It’s a sobering finale for a club that has had high ambitions since it was acquired by Britain’s Ineos in 2019 and has had three top-five finishes since then. Nice were dumped out of the Champions League in the preliminary rounds in August and their season quickly went south.

In November, players, staff, and management had a run-in with hundreds of angry fans gathered outside the training centre. The altercation pushed several players to seek an early exit in the January transfer window.

Nobody gives them a chance against Lens, but history could repeat itself here: as well as the year of their last Cup win, 1997 was also the last year they were relegated.

“It is still a final, so of course we will give our all. But the two matches that come after are more important,” the club’s president Jean-Pierre Rivère acknowledged ahead of the game. “We want to stay in Ligue 1. That is our only ambition.”

(FRANCE 24 with Reuters)